separate reflect & refract overrides

[Buck]

it would be great if the reflection/refraction override (both in the global, as well as in the local material specific) were broken up into two separate overrides, one for reflection and the other for refraction. I have come across several instances where this would be desirable.

[Sushidelic]

second that!

[tom schuelke]

yoop third that

Tom

[Buck]

and on those same lines (actually, I'm not sure that this is possible...) if there would be some sort of reflection/refraction exclude, where you could pick which objects get reflected/refracted in a particular material or object. If it's possible, it would be awesome